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Topic: Diacetyl (Read 1788 times)

I haven't made too many lagers, but this winter I'm trying to make some German Lagers in my basement (Norman Bates room) that is a steady 48. My last two have had diacetyl. My first was a Dunkel with WY 2206 that I added some US 05 to and it turned out fine. My last one (Vienna Lager) with WY 2308 I even did a diacetyl rest for two days then back to cold for awile and I figured that should do it and I carbed it. Next, I taste a sample and there is diacetyl in the aroma and flavor so I warm it up again. The buttery aroma and flavor are still there. I really don't want to dump this before I've tried everything. Does diacetyl vanish over time or should I add more yeast? Also, I have a Doppelbock fermenting on the 2308 slurry and I want to avoid the "butter". Suggestions please.

You need to warm things up, like into the 60s, for about 3 weeks, so that the yeast can eat it. Yeast works better at warm temps than in the cold (of course). If you still have diacetyl after 3-4 weeks, then it becomes permanent and there's not much else you can do except maybe to add a TON more actively fermenting yeast.

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Dave

"This is grain, which any fool can eat, but for which the Lord intended a more divine means of consumption. Let us give praise to our Maker, and glory to His bounty, by learning about... BEER!" - Friar Tuck (Robin Hood - Prince of Thieves)

Next time, pitch half a slurry of yeast from a comparable batch and leave it in the primary for a month - you will likely avoid any hint of diacetyl, as the yeast will clean it up. If you racked right as terminal gravity was reached, the yeast did not have time to clear up the diacetyl. For the current batch, I would warm it to the 60's or even a little warmer than that to get the yeast in action to clean up the butter.

Thanks guys. I have the Vienna at 62 right now and I'll leave it for 2-3 weeks. I 'll leave the Doppelbock in primary for 4-6 weeks, then I'll give it a D-rest for a week and lager for 2 months.

had similar issues...recently discovered in this forum that i was pitching my starter at too high at 60F, and then dropping down to 50F, making it almost certain to produce diacetyl at levels much higher than others who pitch at 45-48F.

you didn't indicate what temp you pitch at, so just wanted to mention it.

Update - I let it warm up for about a week and a half and it is noticably better. I can smell a faint diacetly aroma, but not in the flavor at all. It looks like this one will be OK after all - thanks for the suggestions.